"HRVs bring fresh air — not cold air — into tight homes, but you have to accurately size and balance the ductwork"

In the 20 years that I've been building homes, I've
seen a dramatic rise in the demand for mechanical
ventilation in general and for heat-recovery ventilators
(HRVs) in particular. Much of this demand is
thanks to the growth of
utility-sponsored newconstruction
programs.
These programs recognize
that natural ventilation
is not a reliable way
to provide fresh air for
the people in a modern
home. Mechanical ventilation
is the only reliable
way to do the job.
Despite the new awareness, many builders still think
that ventilating a home means putting in a range hood
and a bath fan. Unfortunately, that's not enough. A
good ventilation system not only removes stale air from
kitchens and baths, but it also supplies an